Anatomical determinants of occipitocervical fusion in skull base chordoma resection: a systematic review of the literature with illustrative cases.

OBJECTIVE: Skull base chordomas are rare, locally osseo-destructive lesions that present unique surgical challenges due to their involvement of critical neurovascular and bony structures at the craniovertebral junction (CVJ). Radical cytoreductive surgery improves survival but also carries significant morbidity, including the potential for occipitocervical (OC) destabilization requiring instrumented fusion. The published experience on OC fusion after CVJ chordoma resection is limited, and the anatomical predictors of OC instability in this context remain unclear. METHODS: PubMed and Embase were systematically searched according to the PRISMA guidelines for studies describing skull base chordoma resection and OC fusion. The search strategy was predefined in the authors' PROSPERO protocol (CRD42024496158). RESULTS: The systematic review identified 11 surgical case series describing 209 skull base chordoma patients and 116 (55.5%) who underwent OC instrumented fusion. Most patients underwent lateral approaches (n = 82) for chordoma resection, followed by midline (n = 48) and combined (n = 6) approaches. OC fusion was most often performed as a second-stage procedure (n = 53), followed by single-stage resection and fusion (n = 38). The degree of occipital condyle resection associated with OC fusion was described in 9 studies: total unilateral condylectomy reliably predicted OC fusion regardless of surgical approach. After lateral transcranial approaches, 4 studies cited at least 50%-70% unilateral condylectomy as necessitating OC fusion. After midline approaches-most frequently the endoscopic endonasal approach (EEA)-at least 75% unilateral condylectomy (or 50% bilateral condylectomy) led to OC fusion. Additionally, resection of the medial atlantoaxial joint elements (the C1 anterior arch and tip of the dens), usually via EEA, reliably necessitated OC fusion. Two illustrative cases are subsequently presented, further exemplifying how the extent of CVJ bony elements removed via EEA to achieve complete chordoma resection predicts the need for OC fusion. CONCLUSIONS: Unilateral total condylectomy, 50% bilateral condylectomy, and resection of the medial atlantoaxial joint elements were the most frequently described independent predictors of OC fusion in skull base chordoma resection. Additionally, consistent with the occipital condyle harboring a significantly thicker joint capsule at its posterolateral aspect, an anterior midline approach seems to tolerate a greater degree of condylar resection (75%) than a lateral transcranial approach (50%-70%) prior to generating OC instability.

Safety and efficacy of sphenopalatine ganglion stimulation for chronic cluster headache: a double-blind, randomised controlled trial.

BACKGROUND: Chronic cluster headache is the most disabling form of cluster headache. The mainstay of treatment is attack prevention, but the available management options have little efficacy and are associated with substantial side-effects. In this study, we aimed to assess the safety and efficacy of sphenopalatine ganglion stimulation for treatment of chronic cluster headache. METHODS: We did a randomised, sham-controlled, parallel group, double-blind, safety and efficacy study at 21 headache centres in the USA. We recruited patients aged 22 years or older with chronic cluster headache, who reported a minimum of four cluster headache attacks per week that were unsuccessfully controlled by preventive treatments. Participants were randomly assigned (1:1) via an online adaptive randomisation procedure to either stimulation of the sphenopalatine ganglion or a sham control that delivered a cutaneous electrical stimulation. Patients and the clinical evaluator and surgeon were masked to group assignment. The primary efficacy endpoint, which was analysed with weighted generalised estimated equation logistic regression models, was the difference between groups in the proportion of stimulation-treated ipsilateral cluster attacks for which relief from pain was achieved 15 min after the start of stimulation without the use of acute drugs before that timepoint. Efficacy analyses were done in all patients who were implanted with a device and provided data for at least one treated attack during the 4-week experimental phase. Safety was assessed in all patients undergoing an implantation procedure up to the end of the open-label phase of the study, which followed the experimental phase. This trial is registered with ClinicalTrials.gov, number NCT02168764. FINDINGS: Between July 9, 2014, and Feb 14, 2017, 93 patients were enrolled and randomly assigned, 45 to the sphenopalatine ganglion stimulation group and 48 to the control group. 36 patients in the sphenopalatine ganglion stimulation group and 40 in the control group had at least one attack during the experimental phase and were included in efficacy analyses. The proportion of attacks for which pain relief was experienced at 15 min was 62·46% (95% CI 49·15-74·12) in the sphenopalatine ganglion stimulation group versus 38·87% (28·60-50·25) in the control group (odds ratio 2·62 [95% CI 1·28-5·34]; p=0·008). Nine serious adverse events were reported by the end of the open-label phase. Three of these serious adverse events were related to the implantation procedure (aspiration during intubation, nausea and vomiting, and venous injury or compromise). A fourth serious adverse event was an infection that was attributed to both the stimulation device and the implantation procedure. The other five serious adverse events were unrelated. There were no unanticipated serious adverse events. INTERPRETATION: Sphenopalatine ganglion stimulation seems efficacious and is well tolerated, and potentially offers an alternative approach to the treatment of chronic cluster headache. Further research is need to clarify its place in clinical practice. FUNDING: Autonomic Technologies.

Neuroradiological and Neuropathological Changes After 177Lu-Octreotate Peptide Receptor Radionuclide Therapy of Refractory Esthesioneuroblastoma.

BACKGROUND AND IMPORTANCE: Olfactory neuroblastoma, also known as esthesioneuroblastoma (ENB), is a malignant neoplasm with an unpredictable behavior. Currently, the widely accepted treatment is inductive chemotherapy, with or without surgery, followed by radiotherapy. Since data on genetics and molecular alterations of ENB are lacking, there is no standard molecularly targeted therapy. However, ENB commonly expresses the somatostatin receptor (SSTR) that is also expressed by neuroendocrine tumors. Peptide receptor radionuclide therapy (PRRT) using radiolabeled somatostatin analogues, such as 177Lu-octreotate, is an effective treatment for the latter. We present the complex neuroradiological and neuropathological changes associated with 177Lu-octreotate treatment of a patient with a highly treatment-resistant ENB. CLINICAL PRESENTATION: A 60-yr-old male presented with an ENB that recurred after chemotherapy, surgery, stereotactic radiosurgery, and immunotherapy. Pathology revealed a Hyams grade 3 ENB and the tumor had metastasized to lymph nodes. Tumor SSTR expression was seen on 68Ga-octreotate positron emission tomography (PET)/computed tomography (CT), suggesting that PRRT may be an option. He received 4 cycles of 177Lu-octreotate over 6 mo, with a partial response of all lesions and symptomatic improvement. Four months after the last PRRT cycle, 2 of the lesions rapidly relapsed and were successfully resected. Three months later, 68Ga-octreotate PET/CT and magnetic resonance imaging indicate no progression of the disease. CONCLUSION: We describe imaging changes associated with 177Lu-octreotate PRRT of relapsing ENB. To our knowledge, this is the first report describing neuropathological changes associated with this treatment. PRRT is a promising therapeutic option to improve the disease control, and potentially, the survival of patients with refractory ENB.

Suprasellar and third ventricular cavernous malformation: Lessons learned in differential diagnosis and surgical planning.

BACKGROUND: While craniopharyngiomas (CPs) are the most common cystic suprasellar lesions in adults, cavernous malformations (CMs) only exceptionally occur in this location and are seldom considered in the differential diagnosis of such lesions. However, unlike CPs, suprasellar CMs are not typically approached via an endoscopic endonasal approach. CASE DESCRIPTION: We present a unique clinical case of suprasellar and third ventricular CM mimicking a CP, posing a major decision-making dilemma at the levels of both preoperative diagnosis and surgical planning. CONCLUSION: This case highlights the importance of carefully considering all the differential diagnoses of sellar pathology to select the most appropriate management strategy and surgical approach.

The Laparoscopically Harvested Omental Free Flap: A Compelling Option for Craniofacial and Cranial Base Reconstruction.

Background Management of craniofacial and cranial base tumors is a challenge due to the anatomic intricacies associated with the calvarium, the pathological diversity of lesions that present, and the potential complications. Clinical outcomes in laparoscopically harvested omentum free flaps for cranial base and craniofacial reconstruction are presented in this paper, in the largest case series to date. Methods A retrospective single-center experience for over 10 years with laparoscopically harvested omentum flaps used to reconstruct craniofacial and cranial base defects. Results A total of 13 patients underwent craniofacial or cranial base reconstruction using laparoscopically harvested omentum free flaps. The mean patient age was 48 years. The anterior skull base represented the most common site of reconstruction. A total of 12 of the flaps survived (92%), with one flap failure due to infection. All patients demonstrated satisfactory aesthetic and functional outcomes. There were no perioperative or intra-abdominal complications. Conclusions The laparoscopically harvested omentum free flap is a safe and effective tool in the armamentarium of the reconstructive surgeon. It is the ideal option to treat complex, three-dimensional subcutaneous defects, such as those encountered in craniofacial and cranial base reconstruction. Its unique angiogenic and immunologic capacity makes it an excellent flap for the previously irradiated and/or infected wound bed.

Frameless and Maskless Stereotactic Navigation with a Skull-Mounted Tracker.

OBJECTIVE: In this series, we present 3 cases that show the use of a skull-mounted tracker for image-guided navigation for anterior skull base surgery and ventricular catheter placement procedures. This system obviates fiducials or face masks during the surgical procedure itself and allows for the performance of facial incisions using the Weber-Ferguson approach. METHODS: Our series presents the use of a novel intraoperative navigational system that uses a skull-mounted tracker to navigated anterior skull base surgery. RESULTS: We present 3 cases using this new system: 1 anterior skull base tumor removal that was operated on without a facemask for navigation and 2 ventricular catheter placement procedures. CONCLUSIONS: Intraoperative image-guided navigation has revolutionized neurosurgery. It undoubtedly increases the surgeon's confidence and the perception of safety. Although fiducials and facial masks are the most widely used tools for intraoperative navigation, their use is associated with certain complications. This technique permits free movement of the head during surgery, which in turn facilitates the exposure of head and neck lesions and expedites the approach to ventricular catheter placement. Our case series shows the precision and ease of our technique, which is less time consuming and less cumbersome than the traditional frame-based stereotaxy. In addition, the skull-mounted tracker system allows improved anatomic localization and shorter operating time and avoids the complications associated with the use of rigid fixating head frames.

Erratum: The Laparoscopically Harvested Omental Free Flap: A Compelling Option for Craniofacial and Cranial Base Reconstruction.

[This corrects the article DOI: 10.1055/s-0036-1597138.].

Intra-arterial cetuximab for the treatment of recurrent unresectable head and neck squamous cell carcinoma†.

IMPORTANCE: Management of recurrent head and neck squamous cell carcinoma is a common and challenging clinical problem in head and neck oncology. OBJECTIVE: Here we present the first reported case of super-selective intra-arterial (SSIA) microcatheter based local delivery of cetuximab for head and neck cancer. This technical report describes the techniques used to deliver the SSIA dose of cetuximab, as well as the patient outcome. DESIGN: This technical report is part of an ongoing Phase I Clinical Trial. SETTING: The New York Head and Neck Institute (NYHNI) is a full-service otolaryngology and neurosurgery department at Lenox Hill Hospital, part of the Northwell Health System. The NYHNI serves a diverse patient population with a wide range of head and neck diseases in a tertiary hospital setting. INTERVENTION: SSIA Cetuximab. PARTICIPANT: A patient presents to our clinic with recurrent unresectable squamous cell carcinoma of the nasopharynx. He is recruited into the first cohort of a phase I clinical trial to assess the safety of SSIA cetuximab, dose starting at 100mg/m2. Adjuvant chemo-radiation therapy is also given. MEASURES: Safety, as measured by toxicity of SSIA cetuximab. RESULTS: SSIA Cetuximab has been demonstrated to be a safe and feasible procedure in this technical report. CONCLUSIONS: This case illustrates technical feasibility and a very preliminary assessment of the safety of a novel delivery of a biologic agent for squamous cell carcinoma of the head and neck, which is part of an ongoing phase I clinical trial. TRIAL REGISTRATION: NCT02438995.

Forearm Cephalic Vein Graft for Short, "Middle"-Flow, Internal Maxillary Artery to Middle Cerebral Artery Bypass.

BACKGROUND: The cervical carotid system has been used as a source of donor vessels for radial artery or saphenous vein grafts in cerebral bypass. Recently, internal maxillary artery to middle cerebral artery bypass has been described as an alternative, with reduction of graft length potentially correlating with improved patency. OBJECTIVE: To describe our experience using the forearm cephalic vein grafts for short segment internal maxillary artery to middle cerebral artery bypasses. METHODS: All vein grafts were harvested from the volar forearm between the proximal cubital fossa where the median cubital vein is confluent with the cephalic vein and the distal wrist. RESULTS: Six patients were treated with internal maxillary artery to middle cerebral artery bypass. In 4, the cephalic vein was used. Postoperative angiography demonstrated good filling of the grafts with robust distal flow. There were no upper extremity vascular complications. All but 1 patient (mortality) tolerated the procedure well. The other 3 patients returned to their neurological baseline with no new neurological deficit during follow-up. CONCLUSION: The internal maxillary artery to middle cerebral artery "middle" flow bypass allows for shorter graft length with both the proximal and distal anastomoses within the same microsurgical field. These unique variable flow grafts represent an ideal opportunity for use of the cephalic vein of the forearm, which is more easily harvested than the wider saphenous vein graft and which has good match size to the M1/M2 segments of the middle cerebral artery. The vessel wall is supple, which facilitates handling during anastomosis. There is lower morbidity potential than utilization of the radial artery. Going forward, the cephalic vein will be our preferred choice for external carotid-internal carotid transplanted conduit bypass.

Management of airway compromise following thyroid cyst hemorrhage after thrombolytic therapy.

The risk of hemorrhage after therapeutic administration of tissue plasminogen activator (tPA) is well known. Cases of postadministration hemorrhage have been reported within many organ systems. We present a case of a 62-year-old female with undiagnosed thyroid goiter who received tPA for acute ischemic stroke and developed acute airway compromise. The surgical airway response team was called due to inability to ventilate or intubate. An incision into the mass during attempted tracheotomy released colloid and blood, decompressing the airway and facilitating ventilation and intubation. Hemithyroidectomy for mass removal was delayed for 3 days to allow normalization of post-tPA coagulopathy.

Internal maxillary artery-middle cerebral artery bypass: infratemporal approach for subcranial-intracranial (SC-IC) bypass.

BACKGROUND: Internal maxillary artery (IMax)-middle cerebral artery (MCA) bypass has been recently described as an alternative to cervical extracranial-intracranial bypass. This technique uses a "keyhole" craniectomy in the temporal fossa that requires a technically challenging end-to-side anastomosis. OBJECTIVE: To describe a lateral subtemporal craniectomy of the middle cranial fossa floor to facilitate wide exposure of the IMax to facilitate bypass. METHODS: Orbitozygomatic osteotomy is used followed by frontotemporal craniotomy and subsequently laterotemporal fossa craniectomy, reaching its medial border at a virtual line connecting the foramen rotundum and foramen ovale. The IMax was identified by using established anatomic landmarks, neuronavigation, and micro Doppler probe (Mizuho Inc. Tokyo, Japan). Additionally, we studied the approach in a cadaveric specimen in preparation for microsurgical bypass. RESULTS: There were 4 cases in which the technique was used. One bypass was performed for flow augmentation in a hypoperfused hemisphere. The other 3 were performed as part of treatment paradigms for giant middle cerebral artery aneurysms. Vein grafts were used in all patients. The proximal anastomosis was performed in an end-to-side fashion in 1 patient and end-to-end in 3 patients. Intraoperative graft flow measured with the Transonic flow probe ranged from 20 to 60 mL/min. Postoperative angiography demonstrated good filling of the graft with robust distal flow in all cases. All patients tolerated the procedure well. CONCLUSION: IMax to middle cerebral artery subcranial-intracranial bypass is safe and efficacious. The laterotemporal fossa craniectomy technique resulted in reliable identification and wide exposure of the IMax, facilitating the proximal anastomosis.

Introducing the tibial-dorsalis pedis osteocutaneous shin flap: a new option for oromandibular reconstruction.

BACKGROUND: The authors investigated the possibility of incorporating a well-vascularized, partial corticotomy of the anterolateral aspect of the tibia "in-series" with a dorsalis pedis fasciocutaneous free flap for oromandibular reconstruction. METHODS: A cadaveric injection study was performed to characterize the vascular territory of the anterior tibial artery with regard to the surrounding osseous and soft tissue. The two-point breaking strength of the tibia (twist) was examined with fracture strain gauge analysis to determine the threshold of tibia corticotomy that would lead to a pathologic fracture. Finally, the authors performed an in vivo prospective clinical examination of the tibial-dorsalis pedis osteocutaneous shin flap. RESULTS: The perfusion study revealed that the anterior tibial artery provided a rich matrix of musculofascial periosteal blood supply to the anterolateral cortex of the tibia that could potentially support free osseous tibial transfer. Two-point osteotomy fracture strain gauge analysis demonstrated that the threshold of tibia corticotomy that would lead to pathologic fracture of the remaining tibia was greater than 30 percent. The osteocutaneous shin flap was performed in eight patients. The mean follow-up was 61 months. There were no cases of flap loss, salivary fistula, nonunion, or tibia pathologic fracture. All patients achieved ambulation. CONCLUSIONS: The authors introduce the osteocutaneous tibial-dorsalis pedis free vascularized flap as a viable option for oromandibular reconstruction. Its most notable advantage is the independent mobility of the skin paddle, in combination with bone stock that replicates mandibular bone dimensions, facilitating primary osseointegration or denture rehabilitation. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Endovascular palliation of multivessel blowout syndrome in the setting of a nonresectable neck sarcoma.

Carotid blowout syndrome is a rare life-threatening complication of head and neck malignancy. Current literature has focused exclusively on the carotid system and associated branches. We present a unique case of multivessel blowout in the setting of a large nonresectable neck sarcoma requiring various endovascular techniques for palliation.

Revising large scars.

Large scars in the head and neck are often the cause of significant emotional distress to patients, and often present unique challenges to the plastic and reconstructive surgeon undertaking their revision. The primary goal of scar revision is to eliminate compromise of function that may have resulted from scar contracture; a secondary goal is to improve the appearance of the scar. Special techniques for the revision of large scars include serial partial excision, rapid intraoperative or prolonged tissue expansion, split- and full-thickness skin grafting, regional flaps, and free microvascular tissue transfer. Recent research has investigated the use of artificial skin and autologous fat grafting for large scar revision.

Mitek anchor-augmented static facial suspension.

OBJECTIVE: To evaluate the efficacy of the Mitek minianchor suture system as an adjunctive procedure for static facial suspension and assess its ability to improve functional and aesthetic outcomes in patients with complete facial paralyses. METHODS: A retrospective review of 5 patients who underwent adjunctive static facial suspension with the Mitek GII minianchor suture system at a tertiary care academic center. A bone anchor in the maxilla connected to 2 suture arms was used. One suture arm elevated the oral commissure on the paralyzed side. The second suture arm adjusted for upper lip segment asymmetry and Cupid's bow deviation, or lateralized the external nasal valve. Outcome was evaluated by photodocumentation and clinical examination. RESULTS: There was an average of 76.9% improvement in vertical symmetry of the oral commissure (range, 43%-100%), an average of 65.0% improvement in horizontal deviation of the Cupid's bow (range, 50%-100%), and an average of 85.3% improvement in symmetry of upper lip segments (range, 67%-100%). All patients experienced improvement in oral-nasal competency. CONCLUSIONS: The Mitek minianchor suture system is a safe and effective adjunctive method to improve facial symmetry and oral-nasal competency in patients with facial paralyses. Its multivector design approximates the ideal positions of key anatomical points of the midface during static facial suspension surgery.

Generation and characterization of functional cardiomyocytes using induced pluripotent stem cells derived from human fibroblasts.

We have successfully developed both spontaneous and inductive cardiomyocyte differentiation of iPS cells reprogrammed from human foreskin fibroblasts. The reprogrammed iPS cells morphologically resemble human cardiomyocytes which can beat. RT-PCR and immunostaining show that cardiac markers are expressed that are comparable to the differentiation pattern of authentic human embryonic stem cells, indicating the existence of both immature and mature differentiated cardiomyocytes. 5-Azacytidine greatly enhanced the efficiency of cardiomyocyte differentiation, whereas dimethylsulfoxide had no effect. Low serum and bone morphogenetic protein-2 marginally improved differentiation efficiency. iPS cell-derived cardiomyocytes changed their beat frequency in response to cardiac drugs, which included ion channel blockers and alpha/beta adrenergic stimulators. Derived cardiomyocytes look promising as an in vitro system for potential drug screen and/or toxicity, making this system closer to practical use in the near future.

Advances in cranioplasty: a simplified algorithm to guide cranial reconstruction of acquired defects.

The search for a universal reconstructive material and the application of a routine approach leaves the surgeon limited in cranial reconstruction. Facility with a variety of implant materials and approaches helps optimize surgical management. The variability of surgical defects and challenges in cranial reconstruction highlights the importance of a strategic approach to evaluate both the defect and the clinical circumstance. Among the numerous alloplastic materials available, the utility of titanium mesh, hydroxyapatite cement, and prefabricated custom acrylic implants have remained at the forefront. The onus of responsibility remains on the surgeon to evaluate each clinical scenario and select the optimal course for management.

Transnasal Transsphenoidal Endoscopic Repair of CSF Leakage Using Multilayer Acellular Dermis.

UNLABELLED: Cerebrospinal fluid (CSF) leaks result from a communication between the subarachnoid space and the upper aerodigestive tract. Because of the risk of complications such as meningitis, brain abscess, and pneumocephalus, all persistent CSF leaks should be repaired. Surgical repair may be achieved transcranially or extracranially using a wide variety of autogenous, allogenic, and synthetic patching materials. We report our results with a transnasal transsphenoidal endoscopic approach for the repair of CSF leaks coupled with a multilayer closure using acellular dermis (Allodermtrade mark). We conducted a retrospective review of all patients presenting to our institution over the past 5 years with isolated sphenoid sinus CSF fistulas. RESULTS: Twenty-one patients were included in the study. Nineteen patients (90.5%) had their sphenoid sinus CSF fistula repaired during the first attempt; 2 patients (9.5%) needed a second attempt. The multilayer repair of the CSF leak using acellular dermis via a transsphenoidal endoscopic approach is an effective and successful method of surgical repair of the fistula site. Neither the number, size, nor cause of the CSF fistula affected surgical outcomes. However, the presence of hydrocephalus was a significant negative variable, altering the surgical outcomes of our patients. The acellular dermis offers the advantage of not requiring autogenous tissue for the effective repair of CSF leaks in the sphenoid sinus.